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  • 2008 Volume 28 Issue 2
    Published: 20 March 2008
      

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  • 论文
    DUAN Xue-Jun, WANG Shu-Guo, CHEN Wen
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    With the rapid economic and social development, population distribution among cities in the Changjiang River Delta has undergone significant changes. Population mobility and migration has come into being the most concentrated contradictions with respect to the population development of the cities in the Changjiang River Delta. Using the methods of density analysis, uneven index, gravity centre analysis and shift-share analysis, this paper studies the characteristics and law of the population distribution evolution in the Changjiang River Delta since the beginning of the reform and open-up of China, and furthermore, sums up to the following four points: First, the population evolution of the cities in the Changjiang River Delta shows different characters in three periods of the year 1980-1990, 1990-1997, 1997-2003. In the first period, the population growth shift is very large, and population distribution is centralized quickly. In the second period, the population uneven index and the population growth shift among the cities are decreased, but the population growth shift among six great regions is increased obviously. In the third period, the population distribution among the cities is centralized, and the shift extent of the population growth is increased. Because the population growth shift among the cities in the south of the Changjiang River is higher than that among the cities in the north of the Yangtze River, the overall population distribution center moves southward. The population growth shifts among the regions on each level are different, the regions’ level is higher, the population growth shift is lower, and the population distribution is inclined to more stable. Since 1990, on the condition of the market economy, although competition to attract the population, especially the high quality population, is very heat among the cities in the Changjiang River Delta, the difference of the population growth speeds of these cities is decreased and the centralization of population distribution comes down. Because of the variety of the position and function in the whole region, the traffic condition, and the level of the economic and social development, etc., Shanghai City, the capitals of Jiangsu and Zhejiang Province get more population growth shift in the study period, and the population is continuously centralized to these cities in this period. Anyway, since the beginning of the reform and open-up of China, the distribution of population among the cities in the region of the Changjiang River Delta has come through the visible change, which are mainly droved by the economic and social development, and it is also significantly affected by the policy of the regional population management.
  • 论文
    WANG Qi, CHEN Cai
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    In the modorn industry period,large-scale industrial production has induced the difference of regional leading economic activities.So,the coexistence of dispersion and agglomeration has become the character of world economic development in the information economy era.Industry cluster is a "viscous point on smoothing space" in the borderless information economy,which is the premise and foundation of coupling(and associaton) between industry cluster and regional economy space.This paper states the meaning of coupling between industry cluster and regional economy space based on the signification of industry cluster and regional economy space.Base on this,it constructs coupling degree and coupling(coordination) degree model between industry cluster and regional economy space by using the synergetic thought of system science and the emergence theory of complex system,and then it summarized the relationship between coupling(coordination) degree of regional economy space and emergence property of system.
  • 论文
    SANG Qiu, ZHANG Ping-Yu, GAO Xiao-Na, XIN Xin
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    Based on factor analysis method and ARCVIEW technology, taking central Liaoning Urban Agglomeration as an example, this paper makes a comprehensive assessment on the socio-economic development at county level, and reveals the actual characteristics and evolving characteristics of spatial disparity of urban agglomeration from 2000 to 2005. The results are as follows. Firstly, factors that mainly influence the interior development differentiation of Central Liaoning Urban Agglomeration are economic scale, social development, and industrial structure. Their weighs are different, and the economic scale had changed from second factor to first one from 2000 to 2005, which indicates that these three factors are not in a harmonious condition and the economy scale had been the main factor to prompt the comprehensive development of the urban agglomeration. Secondly, at county level, estimated by indexes, the absolute differentiation of comprehensive development level is smaller than that of economic scale, social development and industrial structure. Thirdly, Shenyang City and Anshan City have been both centers of Central Liaoning Urban Agglomeration, and north-south disparity and east-west disparity are forming. Fourthly, variability of comprehensive development level of county is severe, and it shows north-south disparity. By and large, comprehensive development level of county decreases step by step from a central county to a marginal county in the administrative region of a city. Finally, most counties were not in the harmonious development condition, and the harmonious degrees of most counties had descended from 2000 to 2005.
  • 论文
    ZHENG Wen-Sheng, DING Si-Bao, WANG Xiao-Fang, LI Tie-Bin
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    The shantytown is the result of city poverty. The resources-dependent city in Northeast China is the representative city of the shantytown and city poverty. The paper puts forward that the emphasis of shantytown reconstruction is to construct the circumstance of antipoverty, and the geography can research slum governance and city antipoverty through the clew of poverty denizen, poverty city zone and poverty city. The allocation uptown moved from the caved-zone in resources-dependent cities brings many problems,for example, the denizen’s living burden is aggravated, the location and scope of allocation uptown is not appropriate, the assistance ability of antipoverty to needy denizen from local government is very poor, and the transformation foreground of city economic is not very affirmative, etc. On the bases of these, many measures should be used in the resources-dependent cities to realize the sustainable shantytown reconstruction and accelerate city antipoverty, which includes advocating the flexible reconstruction pattern, improving location condition of allocation residence, increasing the assistance to poverty denizen from central government, and sustaining to enhance the spontaneity progress ability of resources-dependent cities.
  • 论文
    DONG Li-Jing, ZHANG Ping-Yu
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    An important issue affecting state security and economic prosperity is industrial transformation of the old industrial city in China’s regional economy, yet it still remains uncompletely resolved. Here we investigated the changes in the interaction of industrial transformation and employment in the old industrial city. There are three critical regional features on the changes. Namely, most of the old industrial cities rely heavily on resources-intensive industries and traditional manufacturing industries. Affected by industrial transformation, the workforce allocation of various industries is changing, which is going step further to make a difference on industrial-occupational employment structure. Generally, with the hard condition of layoff and unemployment, it is required to resolve the employment and re-employed problem for the old industrial city, so there are some changes of employment policies and employment institutions during industrial transformation. In addition, regarding the large state-own enterprises (SOEs) as the main part in the old industrial city, the behavior and idea of employee are strongly subject to the restrictions of the unit of enterprise. With accelerating industrial transformation, the employment cultures transfer from conservative culture to enterprise culture, from industrial culture to commercial culture. As a typical old industrial city in China, Shenyang's industrial transformation is a representative one. Shenyang preferentially constructed in the early times of the P.R. China, which has put an emphasis on the development of the secondary industry in terms of economic structure. Moreover, it has been suggested that its employment structure focuses on the secondary industry. With the reform of enterprises deepened constantly, such industries established in the planned economy mode, especially state-owned enterprises (SOEs), have brought a series of problems, such as increased unemployment rates and laid-off employee. Shenyang has thus become one of the major cities in china, with severe employment problems. Based on those cases, this paper explores industrial transformation of Shenyang from perspective of industrial upgrading, industrial replacement and industrial convergence. Then, it analyses employment effect on industrial transformation, which include the change of employment structures, institutions and cultures. The results indicate that there are still structural contradictions of employment and re-employment, though Shenyang has reformed on the state-owned enterprises and urban economy from the mid-1990s. Finally, we discuss the countermeasures of employment enhancement during revitalizing the old industrial base in Northeast China, developing port cities, constructing the new northern developing area and the western industrial corridor of Shenyang, which involve in developing the tertiary industry and diverse nonpublic ownership economies, increasing labor-intensive industries and small and medium-sized enterprises, accelerating reformation of the state-owned enterprises and perfecting the social security system, etc.
  • 论文
    XU Hui, PENG Ping
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    According to situations of regional economic developments of eleven cities in Jiangxi Province, based on the factors of GDP, population scales and spatial distance, using gravity model and 0-1 integral programming model, this text proprosed a view to the division of ecnomic regions in Jiangxi Province. The result of the division indicates that Jiangxi Province can be divided to four economic zones. At the same time,the paper put forward the cooresponding countermeasures and propositions on the coordinated development in the economic zones. The research of this paper provided a new quantitative analysis, with a good application prospect.
  • 论文
    WANG Kai-Yong, CHEN Tian, WANG Li-Yan, YUAN Hong,
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    In the metropolis fringe area, as communications between urban and rural area are intensive, urban space develops rapidly and land use changes sharply. With the rapid urbanization, the effects of city on surrounding areas become more and more obvious. The economic communication between urban and rural area become more and more compact, and the interrelations between them are strengthened constantly. In some developed quasi-urbanization areas, the opportunity of realizing integration of urban and rural area is mature. As a case study, Shuangliu County is analyzed, which is a typical quasi-urbanization area, lying in the fringe area of Chengdu metropolis, and where many factors lead to its imbalance and circle—like spatial structure. Based on the concept of harmonious development of integration of urban and rural area, this paper analyzed the development characteristics of integration of urban and rural area in Shuangliu County, which can be come the base and gist to make harmonious development model of urban and rural integration. Based on the understanding of interrelated relationship and integration trend, it explored the harmonious development model of urban and rural integration in Shuangliu County, which is beneficial to the acceleration of urbanization and realizing the urban and rural integration.
  • 论文
    YAN Hao-Kun
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    The labor interregional mobility in China has important effects on the interregional disparity of China. However, no common conclusion about the labor interregional mobility enlarging or shortening the interregional disparity is drawn from the present researches. Based on the background of institutional transformation of China, this paper suggests that the household register system and the supporting policies endemic to China constructed the system restraints on the labor interregional mobility. These characteristic systems, including the household resister system and the supporting policies, gradually became a kind of "permission system" for those labors who move from one region to another in China. There are two different modes of labor mobility restricted by the "permission system" of ingoing place during the period of institutional transformation of China. One is the mobility of labors qualified above the critical threshold of permission rules of ingoing place, and the other is under. Author calls the former one as the mode of labor migration mobility, and the latter the mode of labor wandering mobility. As the critical threshold of permission rules is mainly the requirement for labor's quality, the labors of high quality always use the mode of labor migration mobility while the labor of low quality can only use the mode of labor wandering mobility. This paper further analyzes the impact of mode of labor mobility on interregional disparity. This research result shows that high quality labors interregional mobility in the period of institutional transformation of China does enlarge the interregional disparity, which is in common with the conclusion of experience. The difference from previous research conclusion is that low quality labors interregional mobility in the period of institutional transformation of China can increase the average income level of comparatively undeveloped areas, and it also enlarge but not shorten the interregional disparity and the rural-urban disparity of China to some extent due to the characteristic system restraints in China.One significant attempt of this paper is to introduce the word "labor quality" into the analysis of the labor interregional mobility. It divides the labor mobility into high quality labor's interregional migration mobility and low quality labor's interregional wandering mobility on the base of the institutional transformation background of China, and further analyzes separately their effects on regional disparity. Therefore, it is probably much more close to the real situation of China, compared with those researches without considering the institutional transformation background of China and the quality differences of the labors who move interregionally. The significance of this paper also includes that author constructs a unified theoretically analytical framework aimed to analyze all kinds of labor mobility in China, which is different from most of the existing research documents.It is known that the rural-urban disparity and regional disparity of China are enlarging in recent years. There are many causes inducing this phenomenon. This paper explains the phenomenon from perspective of the labor interregional mobility, which is possible to help the governments make polices.
  • 论文
    SONG Ge, GAO Nan
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    In recent years, the adjustment of administrative divisions has changed in the city land scale, the land utilization structure and its using way. Adopting scientific and effective methods in appraisal economic benefit of urban land utilization economic benefit become more important. This article takes landuse in Harbin built-up district as the object of research, combining Harbin development as well as the present situation of landuse and construct evaluating indicator system. It takes DEA (Data Envelopement Analysis) as method and operates with Matlab to appraise Harbin land utilization economic benefit from 2001 to 2005. According to the analysis result, it may be seen that Harbin City land utilization economic benefit level is ordinary and its land investment has been sufficient. Accordingly, the article proposes three facets to improve Harbin City land utilization economic benefit, such as strengthening the use of existing urban lands, as well as paying more attention to the investment ratio of different land types and the adjustment of the industrial structure.
  • 论文
    Hasbagen, Li Bai-Sui, BAO Yin, Wu Dun
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    Taking the territory of Hohhot City as the study area, and based on dissipation structure theory and the principle and method of system dynamics, a model of regional population carrying capacity of land resources was developed. The results of the simulation show that the medium scheme is the optimal one, then by 2020 the area of farm land will have been reached to 52.42?104 ha, the area of grassland 61.86?104 ha, the percentage of forest cover 35.04%, the value of GDP at 2789.01?108 yuan (RMB), the population 372.34?104, and all the indexes showed above are between the range of high scheme and low one. From the food-population carrying capacity, the result is low scheme> mudiem scheme>high scheme; from the currency-population carrying capacity, the result is high scheme> mudiem scheme>low scheme; from the population comprehensive carrying capacity, the result is high scheme> mudiem scheme>low scheme. The food-population carrying capacity, currency-population carrying capacity and population comprehensive carrying capacity will be 3.1?106 person, 17.32?106 person and 10?106 person respectively in 2020, which indicate that the contribution of the currency-population carrying capacity to the population comprehensive carrying capacity will exceed that of the food population carrying capacity greatly. The suggestions are taken seriously in development and protection of resources and environment while developing the economy, intensifying the rebuilding of the environment, harmonizing the relationship between the economic development and the environment, making up the insufficiency of food population carrying capacity by developing the economy, improving the population comprehensive carrying capacity and promoting social and economic sustainable development.
  • 论文
    WANG Shen-Min, JIN Xiao-Bin, ZHOU Yin-Kang, ZHANG Wei
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    Land reclamation and readjustment play an important role in keeping dynamic balance of cultivated land amount, while mining subsided land reclamation is one of the important parts. Caused by mining, mining subsided land possesses special characters, such as terrain fragment, undulation of micro-topography, leanness of land nutrient, etc., which make it much more complexity in planning and designing of land reclamation project. Based on the principle and method analysis, we grid the contour lines on the topographic map, and build 3D regular data field based on digital contours to get 3D terrain model, modeling the terrain of the project area. And land reclamation suitability evaluation, project plan and selection and engineering design were discussed, aided by Geographic information system (GIS), to provide method for the planning and designing of the land reclamation project in the future.
  • 论文
    FU Yao, TANG Jie, LIANG Xi-Bo
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    Development area endures big environmental press which comes from urban economy and urban construction as mostly increase pole and carrier of Chinese industrialization and urbanlization advancement. Considering the green land construction status quo, the article indicates that urban construction impropriates green grass land and green land distribute unbalanced, and that green land layout and network are not perfect and characteristic of green land construction do not stand out in development area. Based on this, we set green land rate as 45%, green land area as 35.97m2 per capita, public green land area as 29.24m2 per capita, and green land commanding index of general plan before 2020. We bring green land system space mode of "one ring, two strip, flowing green, line net and gardens" which unites dot, line and side of plan. From landscape ecology factors such as base, corridor, block and so on, we plan green land system construction train of thoughts in different measure.
  • 论文
    MEI Hu
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    After selecting 28 indexes, an evaluation system for social benefit of transportation in Tibet was established, and then the social benefits of aviation, highway and railway were evaluated via the Analytical Hierarchy Process (AHP) and Likert scale in this paper. According to the result, it is evident that the political significance is the most important index in the development of transportation, and there is good social benefit to develop aviation in Tibet. It is also suggested that the constructing of transportation system should be based on conditions of history, geography, and actuality in Tibet. What’s more, the development on each vehicle, combined with their characters, should be taken into account of the relative social benefit of transportation to invest and plan. In terms of the above study, it may be helpful to support a direct, macro control to construct transportation system, and achieve development between transportation and society harmoniously in Tibet.
  • 论文
    FENG Juan, ZHAO Quan-Sheng, XIE Wen-Xia, AN Le-Sheng
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    For more truthfulness to reflect the ecological footprint(EF)and biocapacity of small towns in the same province, the paper synthetically analyzed and compared the merits and shortcomings of Ecological Footprint Model, and proposed pha(provincial hectare)as a new area unit to calculate small towns’ EF. For comparison, the EF within Yancheng Town(2004)was calculated in gha(global hectare)and pha, with both results compared and analyzed. The results showed that the EF within Yancheng Town(2004)was 1.711 ha·cap-1 and the biocapacity was 0.985 ha·cap-1, as a results, the ecological deficit was 0.726 ha·cap-1. If using gha as unit area, the three indices mentioned above were 1.210 ha·cap-1, 1.034 ha·cap-1 and 0.176 ha·cap-1. By comparing the ecological deficit/ surplus of land types within Yancheng Town and Shandong Province, it showed that the cultivated land, residential site and built-up land and forestland of Yancheng Town had ecological surplus, but, wasted land, water field and grassland had ecological deficit. The paper analyzed the main cause of the differences and proposed corresponding countermeasures. By comparing the EF within Yancheng Town, Shandong Province, China and world, it indicated that the ecological situation within Yancheng Town in 2004 was beneficial for a relatively sustainable track of development. It is found that using pha to calculate small towns’ecological footprint is well worth studying in application and some problems of calculation must be improved and perfected.
  • 论文
    ZHAO Xiao-Fan, DAI Li-Min, CHEN Wen-Bo, YU Da-Pao, ZHOU Li
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    In order to discover the similarities and differences of driving forces on cultivated land and construction land changes, based on year-by-year renew investigation and statistical data involving nature, society and economy from 1991 to 2005 in Xinjian County of Nanchang City, driving forces of cultivated land and construction land use changes were analyzed synthetically and quantitatively in terms of mathematical statistics methods. Results indicated that driving factors display difference. Socio-economic factors make negative urge on cultivated land use change, relatively, and positive urge on construction land use change. And the sequences in strength of each socio-economic driving force on cultivated land or construction land show distinction. The similarity was manifested mainly in that the economic development, urbanization level and population growth are main components of all driving factors on cultivated land or construction land. Identically driving main components also displayed discrepancy in order of strength. For cultivated land, the sequence is economic development, population growth and urbanization. However, for construction land, that is economic development, urbanization and population growth. The research results contribute to knowing quantitatively and comparatively driving forces on cultivated land and construction land, and point out a way for land use change mechanism research.
  • 论文
    ZHANG Yan-Guang, LIN Zhen-Shan, LIANG Ren-Jun
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    Land resources carrying capacity security is a very important issue which has a significant influence on the social stability of both a country and a region.Meanwhile,the fluctuation of grain output has a close relation with land resources carrying capacity security.Thereby,the researches on the periods,amplitudes and characteristics of the fluctuation of grain output and its causes are propitious to reduce the intensity of the fluctuation,to eliminate unfavorable factors,and further to keep the stability of grain output to insure land resources carrying capacity security.Empirical Mode Decomposition(EMD) is a powerful method for analyzing the nonlinear and non-stationary time series.Therefore EMD method was introduced to study the fluctuation of grain production in Shandong Province,and the data have been decomposed into two imfs and a residual trend term.The conclusions are drawn: The fluctuations of grain output have 3.5-year,7.5-year,10-year and 20-year time scales.Shown from the residual trend term,the grain output has increased continually since 1949.By using dynamics modeling method,grain yields in future 20 years were simulated.Looking from the grain yield that the Shandong Province grain productivity assumes the trend of escalation and according to the existing farming inventory and the historical trend of development that there is not the grain short problem in Shandong Province.But we cannot depend upon the expansion of sown area to increase the grain yield,to guard against the initiation ecological questions.
  • 论文
    YANG Su-Ying, SUN Feng-Hua, MA Jian-Zhong
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    Determination of the threshold by Gamma distribution function and study on spatial and temporal change of precipitation extremes are based on the daily precipitation data of 93 stations during the period 1959-2002 in Northeast China. The main results are summarized as follows: The precipitation extremes’ thresholds decreased gradually from the southeast littoral areas to the northwestern inland. Precipitation extremes were concentrated in June-September, and the increasing was a catastrophe during the period 1985-2002. The probability of the precipitation extremes successively occurred was greater, in which the neighbouring extremes separated by a time gap of 1-5 days was 23.7%. The total extremes increased especially in the lower reaches of the Songhua River and the Mudanjiang River,and the upper reaches of the Liaohe River,as the same with the precipitantion extreme with the time gap of 1-5 days.
  • 论文
    LI Zong-Xing, HE Yuan-Qing, JIA Wen-Xiong, PANG Hong-Xi, YUAN Ling-Ling, NING Bao-Ying, LIU Qiao, HE Xian-Zhong, SONG Bo, ZHANG Ning-Ning
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    The monsoonal temperate glaciers in China are located in the region of the southeastern Qinghai-Tibet Plateau, and these monsoonal temperate glaciers have obvious response to global change. This study takes "glacier-runoff" system of the Bingchuan River Basin of Hailuogou in Gongga Mountain region as research object, because this area has abundant information and data about glacier change. The research have found two important results: (1) The glaciers in Gongga Mountain have sensitive response to global warming since the early of the 20th century, based on glacier-variation data and mass balance data over the past 100 years; (2) glacial runoff has also sensitively corresponded to global warming since the 1980s, as indicated by observed hydrological and climatic data. In conclusion, there is a "glacier-runoff-global change" organism in monsoonal temperate glacier region of China, therefore, "glacier-runoff" system is very sensitive to global change. And what’s more, the result indicated that global changing is the main cause of glaciers retreat, glaciers ablation and runoff rise.
  • 论文
    ZHANG Jie, LI Dong-Liang, WANG Wen
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    By using high resolution 3″DEM data, precipitation data from May to October of 94 weather stations in the east of Qinghai-Tibet Plateau, based on multivariable stepwise regression method, the estimating model of monthly precipitation are done combined with terrain factors. The result shows that the estimated results of precipitation are very well, relative errors are less than 20%, the correlative coefficient pass the test of 0.95. Under the influence of summer monsoon, the precipitation distribution is different in the north and the south region, and the high value center of precipitation is developed south, moved east and withdraw south, which reflects the transferring law of water-vapor of monsoon. The influence of terrains factors on precipitation is marketable.
  • 论文
    YIN Yi-Xing, XU You-Peng, CHEN Ying
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    China is a country with large flood-prone area, thus the research on flood is of great significance. The theory of complexity has provided completely new method for the research on the complex system of flood disaster. To detect the tendency in the future, we apply the method of information entropy to analyze the flood-affected area variation by using the flood disaster data of the whole country and 31 provinces, municipalities and autonomous regions. The results are as follows. The average flood-affected area and its complexity increased very fast in the 1980s and 1990s of the 20th century, so that flood disaster was more changeable and its uncertainty increased. However, entering the 21st century, both of them relieved or decreased slightly. As for the provinces, the paper discovers the regional character of future’s trend of flood-affected area. The whole country may be classified into two flood intensified regions and two flood alleviated regions. The paper classifies the provinces of the whole country into four ranks according to the flood area tendency, and a map of future’s tendency of flood disaster area is given at the end.
  • 论文
    ZHAO Jing-Bo, NIU Jun-Jie, DU Juan, HUANG Fang
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    According to the measurement of soil moisture underground from zero to six metres of 12-year-old Chinese poplar, 13-year-old Chinese parasol, grassland and the corn land in Xinzhuang Village of Sanyuan, we studied the changes of soil moisture in different soil layers of 0-600 cm under different vegetation. The results show that from the upper to the lower, the soil moisture in artificial forest land changes from high to low, then to high in 2005 and 2006 with normal annual precipitation. The soil moisture in grassland and corn land is about 7% more than that in artificial forest land, and it become more and more downwards. After abundant annual precipitationl of 880 mm in 2003, the average soil moisture in the soil layer of 200-400 cm under 12-year-old Chinese poplar, 13-year-old Chinese parasols in 2005 and 12-year-old Chinese poplar, 13-year-old Chinese parasols in 2006 were higher than those in the dried soil in 2001, which indicates that if the precipitation were increasing, the dried earth layer would become non-dried earth layer. If the annual precipitation were up to 880 mm, the soil moisture could meet the normal growth of artificial forests for about 4 years. Guanzhong Plain and areas with similar annual precipitation are suitable for developing of forests basically. But because of the influence of weak dried earth layer, the forests can’t grow well. According to consuming amount of the soil moisture at 2% per year after the rainy year, weak dried earth layer will appear again under artificial forests in 2007 in Guanzhong Plain if mean annual precipitation is normal. The rainy year is the important supplying period of water for underground water in this area. Water seeping from soil to groundwater is normal in rainy year with a mean annual precipitation about 880 mm and lasting three years after the rainy year.
  • 论文
    HE Si-Yuan, LIU Hong-Yan, REN Ji, YIN Yi
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    The landform-climate-vegetation patterns of forest-steppe ecotone on the southeast of Inner Mongolia Plateau were revealed and the result showed that vegetation distribution was affected by the combination of climate and landform. Regionally, forest community type changed along precipitation gradient from reletively humid areas to arid areas as birch, oak and popular forest, and needle leaved forest was distributed closer to forest drought limit. Locally, broad-leaved forest was distributed mostly on shady slope where evaporation was weak and soil bulk density was low and steppe on sunny slope with strong evaporation. Elm woodland was distributed on sandy land with weak capillary force and little evaporation. Based on these results, we pointed out that first, regionally when choosing tree species, their individualistic precipitation limitation should be in primary consideration; second, in microzone with the range of appropriate precipitation, considering the effects of slope aspect on soil water condition, forest should be nourished on shady slope with an angle of 10 to 40 degree; third, local species, forest density and combination of tree, shrub and grass must be taken into account on both regional and local scale, and it is inappropriate to grow dense forest on sandy land.
  • 论文
    LI Hong-Quan, FAN Guang-Zhou, ZHOU Ding-Wen, HUA Wei, LIU Ya-Qin, LI Xue-Min
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    Based on the monthly Normalized Difference Vegetation Index (NDVI) data that is made by GIMMS workgroup of NASA and the monthly air temperature data from 55 stations in the Qinghai-Tibet Plateau for the period of 1982 to 2001, the change characteristic of spring NDVI and the relationship between the spring NDVI anomaly and the summer air temperature have been studied by using the methods of Empirical Orthogonal Function (EOF), correlation analyse and Singular Value Decomposition (SVD). The results are summarized as follows: (1) Spring vegetation presents obviously increased direction over the Qinghai-Tibet Plateau, especially there are more obvious increase in the north and northwest of the plateau and the vicinity of Xigaz?. The mean and maximum air temperature are increased obviously in the north and northwest of the plateau, and the obvious area of minimum air temperature is located in the mid-east of the plateau. (2) The positive correlation between NDVI and air temperature lags 0 to 3 seasons. (3) The correlative coefficient spatial distribution between spring NDVI and summer mean temperature is consistent with its distribution between spring NDVI and maximal temperature. The obvious region of positive correlation is located in the west and northeast of the plateau. The spatial distribution of positive correlative coefficient between spring NDVI and summer minimal temperature is obvious in the northwest and southeast over the plateau. (4) The plateau summer air temperature has a close connection with the preceding spring NDVI. When spring NDVI is abnormally low (or high) over the plateau, and it is obvious negative (or positive) anomaly in the north and the mid-west of plateau, then the summer mean and maximum air temperature are low (or high) in the whole or great part of the plateau, especially obvious in the west and north of the plateau. The influence of spring NDVI on summer minimum air temperature presents consistent positive correlation in whole area, and the key area is located in the mid-south and southeast of the plateau.
  • 论文
    SHI Xing-Min, LI You-Li, YANG Jing-Chun
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    Manas Lake is located at west of Junggar basin. Manas Lake changes are concerned with tectonic movement, environmental change, drainage development and so on. Based on satellite images, field work and previous research, climate background and tectonic background of Manas Lake changes are analyzed in this paper. Manas Lake change history are discussed from lake surface and location change. There are six high lake surface from the Quaternary Period. The Palaeo-Manas Lake moved from south to north, so Manas Lake basin came in being, and subsequently Manas Lake underwent an evolutionary process from shrink to separation and exhaustion.
  • 论文
    LUO Chuan-Xiu, ZHENG Zhuo, PAN An-Ding, AN Fang-Zhou, BEAUDOUIN Celia, HUANG Kang-You
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    The present study analyzes the pollen distribution in Xinjiang Region. The results show clearly that pollen percentage localities are accordant with their dominant community of vegetation. Artemisia pollen has relative high percentage on the Kunlun Mountains, the Altay Mountains and around Junggar Basin. Chenopodiaceae pollen occur widely on the Altay Mountains, Junggar Basin, the Tianshan Mountains and the Kunlun Mountains. Ephedra and other shrub pollen occur highly around Tarim Basin. The distribution of tree pollen, such as Picea, Betula , is mainly on the Altay Mountains and the Tianshan Mountains. The results of cluster analysis can reflect the main ecology assembalges of plant communities in study area. The result of principal component analysis confirms that the distribution of steppe and shrub pollen are mainly controlled by hydrology and humidity factors in study area.
  • 论文
    XIE Yuan-Yun, LI Chang-An, WANG Qiu-Liang, YING Hong-Fu
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    The evidence of human activities around Jiangling area was revealed by sporo-pollen records from sediments in the Jiangling section, Hubei Province. The preliminary human activities started from about 6 200 yr B.P., marked by cultivation on economic crop Papaverraceae and the increased occurrence of pasture plant, such as Labiatae and Plantago. The increased herbs of pasture and crop suggested the primitive stockbreeding and agriculture in the study region. The human activities increased from about 4 700 yr B.P. The broad-leaved trees of Betula and Ulmus, and the aquatic herbs of Myriophyllum, and the spore of Selaginella and Microlepria, started to appear continuously in large amounts, and the weed plants of Artemisia had a speedy increase. The human activities were mainly agricultural planting and grazing near settlement, yet with small piece of economic trees. The large-scale human activities started from 3 400 yr B.P., the Gramineae content ascended fleetly, suggesting the extension of farmland around the lake shore. The broad-leaved trees of Betula, Ulmus, and the herbs of Papaverraceae, Labiatae, Plantago, Artemisia, Chenopodiaceae, Myriophyllum, and the spore of Selaginella, Microlepria had a evident increase. The increases in broad-leaved trees and weed herbs indicate the expansion of settlement around which broad-leaved trees were replanted. The extension of settlement and the enhancement of human activities resulted in the enhanced erosion of surface soil and the increase of coarse particle matters from land and nutritive material. The lacustrine sediments were characterized by the prompt increase of coarse materials, and frequent fluctuation of different forms of grain size, and high value of TOC, TN, and C/N, and low value of organic matter δ13C. The sedimental environment came to evident variance after 2 500 yr B.P., that is, lacustrine and limnic deposit became to floodplain deposit, and human evacuate from Jiangling area by degrees.
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    YAN Wu-Jiu
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    On the basis of the data on As, Hg, Pb, Cd, Zn, Cr heavy metal contents of soils sampled from 14 depth profiles in the periurban zone of Wuhu City, Anhui Provice, the status of soil pollution by heavy metals was studied by use of background contents of these elements under the natural soil condition. Meanwhile, the correspondence analysis method was applied to studing spatial differentiation of metal heavy pollution of the sample soils. The study indicates that on the whole the most of heavy metal existing in the sample soils quite resulted in obvious pollution. Different features of pollution were revealed in different regions. In general, the pollution is more serious in Jiujiang, Matang, and Xijiang area than in the other regions. It was also demonstrated that there was no significant spatial differentiation in contents of heavy metals in the soils, except Pb and Hg.
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    YUAN Mao, DONG De-Ming, HUA Xiu-Yi, ZHANG Li-Hui
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    Water samples were taken from four main river systems, i.e. Songhuajiang River system, Tumenjiang River system, Yalujiang River system and Liaohe River system, in Jilin Province in year 2005 and 2006, and the permanganate values(PV), chemical oxygen demand(COD)values and total organic carbon(TOC)values were measured for these samples, respectively. The quantitative relationships between PV and TOC, COD and TOC, and COD and PV values of water samples collected from the four river systems were analyzed using the linear least square regression method and the significance levels were also tested. Based on these analyses, the models that described these relationships were also established. The results indicate that there are significant linear correlations between PV and TOC, COD and TOC, and COD and PV values of the four river systems. Due to the different location and the different composition, these relationships between PV and TOC, COD and TOC, COD and PV values of different river systems are distinctive. Comparatively, PV value is more suitable to describe less polluted water while COD value is more suitable to be used for polluted water, but TOC value is the best one of the three parameters which can reflect the pollution condition of the water samples more factually.
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    ZHANG Zhong-Sheng, WANG Qi-Chao, SHAO Zhi-Guo, ZHANG Lei, ZHANG Xiu-Wu
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    With economic development, a dam will be built on the Hadashan, which was on the downstream of the Second Songhua River. The total mercury contents in sediments, those in water and the different mercury contents in water of ten sample sites were investigated in order to discuss the impact of the dam on the mercury pollution of the reservoir which would form after the dam was finished. It showed that the suspend particles would deposit resulted from the hydrological conditions changed, which led to the rise of total mercury contents in the reservoir formed by the dam. In the reservoir, the mercury would be sunk. Total mercury contents in water of the drainage site of the reservoir would reduce to 0.032μg/L. The reservoir would be imported in 4.37 kg mercury in the processed particles and 856.8kg mercury in the suspend particles every year. About 1.23cm depth of sediment would be formed by the bedload transported by water in the bottom of the reservoir. The total mercury of re-suspend particles in the upstream of the reservoir and the released mercury in the submerge area have no significantly impact on the mercury pollution of the reservoir.
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    YUAN Li-Feng
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    In order to improve the limitation of traditional debris flow hazard assessment methods, a SVM-based debris flow hazard assessment method was proposed. Seven factors including the most volume of once flow (L1), frequency (L2), watershed area (S1), valley length (S2), watershed relative height difference (S3), valley incision density(S6) and the length ratio of sediment supplement (S9) were chosen as assessment factors of debris flow hazard degree. Using support vector machine (SVM) theory, selecting Radial Basis Function, and using trial-and-error method for optimal selection of parameters, C=8, r=2. Thirty seven debris flow channels with 259 basic data in Yunnan Province were selected as training samples, and an assessment model based on SVM was created. The model was applied to evaluating debris flow hazard degree of Jishi Valley hydropower station of Huanghe (Yellow) River. Assessment result consistency came to 73.33% comparing to fuzzy mathematic method. The results show that the model has advantage of best generation, high training speed, and convenient for modeling through an instance application. It will be thought as being broad application scope that SVM was applied to hazard assessment of debris flow.